A former Power Rangers actor charged with stabbing his California roommate to death with a sword has pleaded not guilty to murder.

City News Service says Ricardo Medina, 37, entered the plea in Lancaster. He could face 26 years to life in prison if convicted.

Former Power Rangers actor Ricardo Medina Jr has pleaded not guilty to murder. Picture: InstagramSource:Supplied

Former Power Rangers actor Ricardo Medina Jr at the start of his career. Picture: SuppliedSource:Supplied

Prosecutors say Medina stabbed Joshua Sutter several times in the abdomen last year at their house in Green Valley, a mountain town north of Los Angeles. The two allegedly were arguing over Medina’s girlfriend and the way she parked her car.

Medina and his girlfriend returned to his room, but when Sutter tried to follow them, the actor grabbed a sword near his bedroom door and stabbed him, prosecutors said.

Authorities say after the attack, Medina called police and waited for them to arrive.

Sutton later died in hospital.

Joshua Sutter died after he was stabbed in January 2015. Picture: ABCSource:Supplied

Medina claimed he was acting in self defence and was released only to be arrested again in January this year.

Medina played the Red Lion Wild Force Ranger on Power Rangers Wild Force’ in 2002. He was the voice of Deker on Power Rangers Samurai in 2011 and 2012.

Ricardo Medina Jr. participates in the 2012 Power Morphicon 3 held at the Pasadena Convention Centre. Picture: GettySource:Getty Images

Ricardo Medina Jr. also had roles in ER and CSI: MiamiSource:Getty Images

“He is a great friend and a great client. It’s something I can’t even conceive. I don’t see that in him. He was a very helpful guy and great with his dog. It’s such a shock,” said Gar Lester, Medina’s former agent who has known the actor for 12 years